Deltaic: Pertaining to or characterized by a delta (the low, nearly flat, alluvial tract of land at or near the mouth of a river, commonly forming a triangular or fan-shaped plain of considerable area, crossed by many distributaries of the main river, perhaps extending beyond the general trend of the coast, and resulting from the accumulation of sediment supplied by the river in such quantities that it is not removed by tides, waves, and currents). (Definition from Jackson, J.A., ed., 1997, Glossary of geology [4th ed.]: Alexandria, Va., American Geological Institute, 769 p.)